This invention generally relates to electronic systems and in particular it relates to operational amplifiers.
An operational amplifier circuit includes: a first differential pair of a first conductivity type having a first current branch and a second current branch; a second differential pair of a second conductivity type having a first current branch and a second current branch; a first current mirroring device coupled between the first branch of the first differential pair and the second branch of the second differential pair for combining the currents from these two branches; and a second current mirroring device coupled between the first branch of the second differential pair and the second branch of the first differential pair for combining the currents from these two branches.